Mapping and Tracking Early Stage Damage and Damage Precursor Conditions

Power plant components are vulnerable to a variety of age-related damage mechanisms. For example, Primary Water Stress Corrosion Cracking (PWSCC) has proven to be a persistent problem for primary system components made of Alloy 600. Leaks in Control Rod Drive Mechanisms (CRDMs) from PWSCC have forced a number of plants to replace reactor vessel heads, at a cost to the industry that was estimated to exceed $1 billion. This project will develop an enhanced damage assessment capability for PWSCC by adapting technology for producing spatially-registered, high-resolution digital images. In particular, the approach will address the need for enhanced condition monitoring by significantly improving the ability to map and track early stage damage conditions in critical plant components, using time-sequenced, spatially-registered digital images of material properties. Commercial Applications and other Benefits as described by the awardee: The use of advanced space-time filtering techniques with time-sequenced digital images of material properties has the potential to substantially increase the capability of detecting and monitoring early stage damage to key plant components, such as CRDM nozzles and J-welds. The technology would enable power plant owners to prevent catastrophic equipment failures, control maintenance scheduling, reduce operating costs, and improve safety margins.